What Is Latency?
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What Is Latency?
Latency is the time it takes for a piece of data to travel from your device to its destination — a website, a game server, a video call — and back. It's measured in milliseconds (ms) and is often what people mean when they complain about "lag." Low latency means near-instant responses; high latency means a noticeable delay between an action and its result, such as a click that takes a moment to register or a video call where voices lag behind lip movement.
Latency is different from bandwidth: bandwidth is how much data can flow at once (like the width of a pipe), while latency is how long it takes for data to make the round trip (like the length of the pipe). You can have high bandwidth and still suffer from high latency, which is why a "fast" internet plan doesn't always fix laggy video calls or online games.
What Causes High Latency?
- Physical distance: the further your data has to travel to a server, the longer the round trip takes.
- Network congestion: too many devices or too much traffic sharing the same connection.
- Outdated or weak Wi-Fi routers that struggle to handle multiple connected devices.
- Poor quality ISPs or overloaded infrastructure that add delay at each network hop.
How to Reduce Latency
Practical fixes include connecting via a wired Ethernet cable instead of Wi-Fi where possible, using a router positioned centrally and away from interference, choosing servers or CDNs geographically closer to your users, upgrading outdated networking hardware, and prioritising business-critical traffic (like video calls) with Quality of Service (QoS) settings. For businesses running cloud applications or VoIP phone systems, a professionally configured network is often the single biggest factor in eliminating lag.